A computer network is a collection of interconnected computing devices that exchange data and share resources. In a packet-based network, such as the Internet, the computing devices communicate data by dividing the data into small blocks called packets, which are individually routed across the network from a source device to a destination device. The destination device extracts the data from the packets and assembles the data into its original form. Dividing the data into packets enables the source device to resend only those individual packets that may be lost during transmission.
Certain devices within the network, such as routers, contain routing unit s that maintain routing information describing routes through the network. Each route defines a path between locations on the network. From the routing information, a forwarding engine of the routers generates forwarding information, which is used by the routers to relay packet flows through the network and, more particularly to relay the packet flows to a next hop. In reference to forwarding a packet, the “next hop” from a network router typically refers to a neighboring device along a given route. Upon receiving an incoming packet, the router examines information within the packet to identify the destination for the packet. Based on the destination, the router forwards the packet in accordance with the forwarding information.
Large computer networks, such as the Internet, often include many routers that exchange routing information according to a defined routing protocol, such as the Border Gateway Protocol (BGP). When two routers initially connect, the routers exchange routing information and generate forwarding information from the exchanged routing information. Particularly, the two routers initiate a routing communication “session” via which they exchange routing information according to the defined routing protocol. The routers continue to communicate via the routing protocol to incrementally update the routing information and, in turn, update their forwarding information in accordance with changes to a topology of the network indicated in the updated routing information. For example, the routers may send update messages to advertise newly available routes or to indicate routes that are no longer available. However, updating the routing information and performing other administrative tasks may consume significant computing resources, limiting the amount of computing resources available to forward traffic.
Conventionally, network administrators scale up the computing resources by adding processors, memory, etc. However, the number of computing resources that can be added within a single chassis is limited. As the number of processors and other computing resources increase, the amount of heat produced and the amount of electricity required also increase. The cooling and power capabilities of a single chassis of a network device may be overwhelmed, which has resulted in network administrators using a separate chassis to provide the additional computing power required to maintain the desired network throughput while the network device performs the various administrative tasks. The network administrator must manage each additional chassis as a separate device, increasing the complexity of managing the network devices. Further, the operating system executing on the network device can only support up to a maximum number of computing resources and software processes, limiting the total computing capacity that may be available to any network device.